1941 - The Shah's pro-Axis allegiance in World War II leads to the Anglo-Russian occupation of Iran and the deposition of the Shah in favour of his son, Mohammad Reza Pahlavi.

1950 - Ali Razmara becomes prime minister and is assassinated less than nine months later. He is succeeded by the nationalist, Mohammad Mossadeq.

1951 April - Parliament votes to nationalise the oil industry, which is dominated by the British-owned Anglo-Iranian Oil Company. Britain imposes an embargo and a blockade, halting oil exports and hitting the economy. A power struggle between the Shah and Mossadeq ensues and the Shah flees the country in August 1953.

1953 August - Mossadeq is overthrown in a coup engineered by the British and American intelligence services. General Fazlollah Zahedi is proclaimed as prime minister and the Shah returns.

Campaign to modernise

1963 January - The Shah embarks on a campaign to modernise and westernise the country. He launches the 'White Revolution', a programme of land reform and social and economic modernisation. During the late 1960's the Shah became increasingly dependent on the secret police (SAVAK) in controlling those opposition movements critical of his reforms.

1978 September - The Shah's policies alienate the clergy and his authoritarian rule leads to riots, strikes and mass demonstrations. Martial law is imposed.

Ayatollah Khomeini

Shah exiled, Khomeini returns

1979 January - As the political situation deteriorates, the Shah and his family are forced into exile.

1979 November - Islamic militants take 52 Americans hostage inside the US embassy in Tehran. They demand the extradition of the Shah, in the US at the time for medical treatment, to face trial in Iran.

1979 1 February - The Islamic fundamentalist, Ayatollah Ruhollah Khomeini, returns to Iran following 14 years of exile in Iraq and France for opposing the regime.

1979 1 April - The Islamic Republic of Iran is proclaimed following a referendum.

1980 January - Abolhasan Bani-Sadr is elected the first President of the Islamic Republic. His government begins work on a major nationalization programme.

1980 July - The exiled Shah dies of cancer in Egypt.

Iran-Iraq war

1980 22 September - Start of Iran-Iraq war which lasts for eight years.

1981 January - The American hostages are released ending 444 days in captivity.

1985 - After the US and Soviet Union halted arms supplies, the US attempted to win the release of hostages in Lebanon by offering secret arms deals, this would later become known as the Iran-Contra affair.

1988 July - 290 passengers and the crew of an Iran Air Airbus are mistakenly shot down by the USS Vincennes.

Ceasefire

1988 July - Iran accepts a ceasefire agreement with Iraq following negotiations in Geneva under the aegis of the UN.

Mohammad Khatami

1997 May - Mohammad Khatami wins the presidential election with 70% of the vote, beating the conservative ruling elite.

1998 September - Iran deploys thousands of troops on its border with Afghanistan after the Taleban admits killing eight Iranian diplomats and a journalist in Mazar-e Sharif.

Student protests

1999 July - Pro-democracy students at Tehran University demonstrate following the closure of the reformist newspaper 'Salam'. Clashes with security forces lead to six days of rioting and the arrest of more than 1,000 students.

2000 February - Majlis elections. Liberals and supporters of Khatami wrest control of parliament from conservatives for the first time.

2000 April - The judiciary, following the adoption of a new press law, bans the publication of 16 reformist newspapers.

2000 May - Inauguration of the Sixth parliament.

Khatami's second term

2001 June - President Khatami re-elected.

2002 January - US President George Bush describes Iraq, Iran and North Korea as an "axis of evil", warning of the proliferation of long-range missiles being developed in these countries. The speech causes outrage in Iran and is condemned by reformists and conservatives alike.

2003 September - UN nuclear watchdog, IAEA, gives Tehran weeks to prove it is not pursuing an atomic weapons programme.

2003 October - Shirin Ebadi becomes Iran's first Nobel Peace Prize winner; lawyer and human rights campaigner became Iran's first female judge in 1975 but was forced to resign after 1979 revolution.

2003 November - Iran says it is suspending its uranium enrichment programme and will allow tougher UN inspections of its nuclear facilities. IAEA concludes there is no evidence of a weapons programme.

2003 December - 40,000 people are killed in an earthquake in south-east Iran; the city of Bam is devastated.

Conservative resurgence

2004 February - Conservatives regain control of parliament in elections. Thousands of reformist candidates were disqualified by the hardline Council of Guardians before the polls.

Nuclear crisis

2005 August-September - Tehran says it has resumed uranium conversion at its Isfahan plant and insists the programme is for peaceful purposes. IAEA finds Iran in violation of the nuclear Non-Proliferation Treaty.

Supporter of Lebanese militia

Iran is an ally of Lebanon's powerful Shia Muslim Hezbollah group

Tehran says its support is moral, political

Israel, US accuse Iran of supplying arms

Group emerged in 1980s with financial backing from Iran

2004 June - Iran is rebuked by the IAEA for failing to fully cooperate with an inquiry into its nuclear activities.

2004 November - Iran agrees to suspend most of its uranium enrichment under a deal with the EU.

2007 July - Iran announces plans to stop making cars that only run on petrol and switch to dual-fuel vehicles, which also run on gas.

Iran agrees to allow inspectors to visit the Arak nuclear plant following talks with the IAEA.

New sanctions

2007 October - US announces sweeping new sanctions against Iran, the toughest since it first imposed sanctions almost 30 years ago.

2007 December - A new US intelligence report plays down the perceived nuclear threat posed by Iran.

2008 February - Iran launches a research rocket to inaugurate a newly built space centre. Washington describes the launch as "unfortunate".

2008 March - President Ahmadinejad makes unprecedented official visit to Iraq, where he calls on foreign troops to leave. He also stresses his government's desire to help rebuild Iraq and signs a number of cooperation agreements.

Conservatives win over two-thirds of seats in parliamentary elections in which many pro-reform candidates were disbarred from standing. The conservatives include supporters of President Ahmadinejad as well as more pragmatic conservatives who oppose his confrontational foreign policy.

UN Security Council tightens economic and trade sanctions on Tehran.

2008 May - IAEA says Iran is still withholding information on its nuclear programme.

Iran's new parliament elects former nuclear negotiator Ali Larijani as its speaker.

Incentives offered

2008 June - EU foreign policy chief Javier Solana presents an offer of trade benefits, which Tehran says it will look at, but will reject if it demands suspension of uranium enrichment.

2008 July - Iran test-fires a new version of the Shahab-3, a long-range missile it says is capable of hitting targets in Israel.

2008 August - Informal deadline set by Western officials for Iran to respond to package of incentives in return for halt in nuclear activities passes without reply.

Iran says it has successfully launched a test rocket capable of carrying a satellite into space.

2008 September - UN Security Council passes unanimously a new resolution reaffirming demands that Iran stop enriching uranium, but imposes no new sanctions. The text was agreed after Russia said it would not support further sanctions.

Relations with US

2008 November - Parliament votes to dismiss the interior minister, Ali Kordan, who admitted that a degree he said he held from Oxford University was fake. The move is a blow to President Ahmadinejad ahead of next year's presidential election.

Disputed election

In an unprecedented move, President Ahmadinejad congratulates US president-elect Barack Obama on his election win. Mr Obama has offered to open unconditional dialogue with Iran about its nuclear programme.

2008 December - Police raid and close the office of a human rights group led by the Nobel Peace Prize winner, Shirin Ebadi. Officials say the centre is acting as an illegal political organization.

2009 February - Speaking on the 30th anniversary of the Islamic revolution in Iran, President Mahmoud Ahmadinejad says he would welcome talks with the US as long as they are based on "mutual respect".

2009 March - Supreme Leader Ali Khamenei tells anti-Israel rally that US President Obama is following the "same misguided track" in Middle East as President Bush.

2009 April - An Iranian court finds Iranian-American journalist Roxana Saberi guilty of spying for the US. She is sentenced to eight years in prison.

2009 May - Iran rejects a US state department report saying it remains the "most active state sponsor of terrorism" in the world.

Election protests

2009 June - Mahmoud Ahmadinejad is declared to have won a resounding victory in the 12 June presidential election. The rival candidates challenge the result, alleging vote-rigging. Their supporters take to the streets, and at least 30 people are killed and more than 1,000 arrested in the wave of protests that follow.

The Iranian authorities claim foreign interference is stoking the unrest, and single out Britain for criticism.

2009 July - President Ahmadinejad dismisses his most senior vice-president, Esfandiar Rahim Mashaie, under pressure to do so by Supreme Leader Ayatollah Ali Khamenei.

2009 August - Mahmoud Ahmadinejad sworn in for second term as president, presents cabinet - the first since the founding of the Islamic Republic in 1979 to include women.

A number of senior opposition figures are accused of conspiring with foreign powers to organise unrest and are put on trial.

Supreme Leader Ayatollah Ali Khamenei says there is no proof that opposition leaders blamed for the post-election unrest were agents of foreign powers.

Missile tests

2009 September - Iran admits that it is building a uranium enrichment plant near Qom, but insists it is for peaceful purposes.

Montazeri dies

A leading figure of the 1979 revolution, Grand Ayatollah Montazeri became a vocal critic of the system

The country test-fires a series of medium- and longer-range missiles that put Israel and US bases in the Gulf within potential striking range.

2009 October - Five permanent UN Security Council members plus Germany offer Iran proposal to enrich its uranium abroad.

2009 November - Iran refuses to accept the international proposal to end the dispute over its nuclear programme. UN nuclear watchdog IAEA passes a resolution condemning Iran for developing a second uranium enrichment site in secret.

Iran denounces the move as "political" and announces plans to create 10 more uranium enrichment facilities.

2009 December - Death of influential dissident cleric Grand Ayatollah Hoseyn Ali Montazeri triggers further clashes between opposition supporters and security forces. At least 8 people die in what is the worst violence since the contested presidential election.

2010 January - Iran executes two men arrested during the period of unrest that followed the disputed presidential election of June 2009. It also puts 16 people on trial over the Ashura Day opposition protests in December, when eight people were killed.

Iranian physics professor Masoud Ali-Mohammadi is killed in a bomb attack in Tehran. No group claims responsibility. The government accuses the US and Israel of his death, while Iranian opposition groups say Mr Mohammadi supported one of their candidates in last year's presidential election.

2010 February - Iran says it is ready to send enriched uranium abroad for further enrichment under a deal agreed with the West. The US calls on Tehran to match its words with actions.

Opposition leader Mir Hossein Mousavi says the opposition will continue its peaceful struggle against the government.

2010 May - Iran reaches a deal to send uranium abroad for enrichment after mediation talks with Turkey and Brazil; Western states respond with scepticism, saying the agreement will not stop Iran from continuing to enrich uranium.

More sanctions

2010 June - UN Security Council imposes fourth round of sanctions against Iran over its nuclear programme, including tighter financial curbs and an expanded arms embargo.

2011 November - A report by the UN nuclear watchdog, the IAEA says Iran is carrying out research that can only be used to develop a nuclear bomb trigger. Iran rejects the findings as politically motivated.

2011 November/December - Protesters attack the British embassy in Tehran after London imposes tighter economic sanctions. Britain evacuates its diplomatic staff and expels all Iranian diplomats, but ties are not severed.

2012 January - US imposes sanctions on Iran's central bank, the main clearing-house for its oil export profits. Iranian threatens to block the transport of oil through the Strait of Hormuz.

Iran begins enriching uranium at its undergound Fordo plant, in what the US terms a "further escalation" in the nuclear row. The European Union imposes an oil embargo on Iran over its nuclear programme.

2012 February - International Atomic Energy Agency (IAEA) inspectors leave Iran after being denied access to the Parchin site, south of Tehran.

Canada breaks off diplomatic relations over Iran's nuclear programme and support for the Assad government in Syria.

2012 October - Iran's rial currency falls to a new record low against the US dollar, having lost about losing 80% of its value since 2011 because of international sanctions. Riot police attack about 100 currency traders outside the Central Bank.

EU countries announce further sanctions against Iran over its nuclear programme, focusing on banks, trade and crucial gas imports.

Rouhani becomes president

2013 September - President Rouhani tells US broadcaster NBC that Iran will never build nuclear weapons, and repeats offer of "time-bound and results-oriented" talks on the nuclear question in his address to the UN General Assembly.

2013 November - Iran agrees to curb uranium enrichment above 5% and give UN inspectors better access in return for about $7bn in sanctions relief at talks with the P5+1 group - US, Britain, Russia, China, France and Germany - in Geneva.

2014 January - World powers and Iran begin implementing a deal on Iran's nuclear programme following intense talks in Geneva.

2014 April - The International Atomic Energy Agency says Iran has neutralised half of its higher-enriched uranium stockpile, as per a deal agreed earlier in the year.

The US refuses to issue a visa to Hamid Aboutalebi, Iran's nominee for ambassador to the United Nations, over his involvement in the seizure of the US embassy in Tehran in 1979.

Iraq crisis

2014 June - President Rouhani says Iran is ready to assist the Iraqi government in its battle against extremist Sunni insurgents, amid reports that Iranian Revolutionary Guards are in Iraq providing military training and advice.

The UK says it plans to re-open the British embassy in Tehran. Full diplomatic relations with Iran were suspended after attacks on the embassy in 2011.

2014 July - The sixth and final round of nuclear negotiations between Iran and the P5+1 group begin in Vienna.

2014 August - Iran says it has shot down an Israeli drone near the Natanz uranium enrichment site.

2014 November - Russia agrees to build up to eight nuclear reactors in Iran, in move that might ease Iranian demands to have own uranium enrichment.

Vienna negotiations on Iran's nuclear programme fail to finalise preliminary deal signed in Geneva in November 2013. The two sides express confidence that remaining sticking points can be resolved, and agree a seven-month extension to the talks.